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Bioprospecting of Ten Microalgae Species Isolated from Saline Water Lake for Evaluation of the Biodiesel Production

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BioEnergy Research
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Sara Khosravinia
Sara Khosravinia
Sara Khosravinia
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Saeid Malekzadeh Shafaroudi at Ferdowsi University of Mashhad
Saeid Malekzadeh Shafaroudi
Abdolreza Bagheri
Abdolreza Bagheri
Abdolreza Bagheri
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Assieh Behdad at Ferdowsi University of Mashhad
Assieh Behdad
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Abstract and Figures

Algal bioprospecting in ecosystems leads to exploring native microalgae and the competency evaluation of economically producing lipids as biofuel or nutritional applications. In this study, ten microalgae species were screened from the saline water lake. Chlorella vulgaris, Chlorella sorokiniana, Chlamydomonas raudensis, Chlamydomonas hedleyi, Dunaliella salina, Picochlorum bazangan sp. nov., Tetraselmis bazangan sp. nov., Haematococcus lacustris, Nannochloropsis oceanic, and Scenedesmus rubescens were isolated and identified using 18SrDNA and tufA markers. Biodiesel potentials were assayed by the determination of biomass productivity, biochemical components, fatty acid profile, and biodiesel properties. The results showed that the maximum biomass yield (1.22 g/L) belonged to C. vulgaris. The highest protein, carbohydrate, chlorophyll, and carotenoid content were recorded in C. vulgaris, C. raudensis, C. sorokiniana, and D. salina, respectively. N. oceanica accumulated high lipid content and omega-3 fractions (31.09%). However, C. hedleyi had the highest lipid productivity (11.64 g/L/day) compared to other microalgae. The best species for biodiesel production was C. vulgaris, with a specific growth rate of 0.36 day⁻¹, lipid productivity of 7.45 g/L/day, and C16-C18 fatty acid profile of 78.3%. The microalgae C. vulgaris had appropriate biodiesel properties of low viscosity (4.49), high cetane number (55.38), and relatively low cloud point (4.98). Another choice was N. oceanic, with high lipid productivity, cetane number (59.79), oxidative stability (56.43), and low iodine value (47.11). Microalgae T. bazangan sp. nov. had a cetane number (55.24), low cloud point (4.71), and C16-C18 fatty acid profile of 82.34%. Accordingly, C. vulgaris, T. bazangan sp. nov., and N. oceanic can be considered potential species for biodiesel.
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Vol:.(1234567890)
BioEnergy Research (2024) 17:1090–1103
https://doi.org/10.1007/s12155-023-10707-2
1 3
Bioprospecting ofTen Microalgae Species Isolated fromSaline Water
Lake forEvaluation oftheBiodiesel Production
SaraKhosravinia1· SaeidMalekzadeh‑Shafaroudi1 · AbdolrezaBagheri1· AssiehBehdad2· NasrinMoshtaghi1
Received: 7 August 2023 / Accepted: 22 November 2023 / Published online: 26 December 2023
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023
Abstract
Algal bioprospecting in ecosystems leads to exploring native microalgae and the competency evaluation of economically
producing lipids as biofuel or nutritional applications. In this study, ten microalgae species were screened from the saline
water lake.Chlorella vulgaris,Chlorella sorokiniana,Chlamydomonas raudensis,Chlamydomonas hedleyi,Dunaliella
salina, Picochlorum bazangan sp. nov.,Tetraselmis bazangan sp. nov.,Haematococcus lacustris,Nannochloropsis oce-
anic, andScenedesmus rubescenswere isolated and identified using 18SrDNA andtufA markers. Biodiesel potentials were
assayed by the determination of biomass productivity, biochemical components, fatty acid profile, and biodiesel properties.
The results showed that the maximum biomass yield (1.22g/L) belonged toC. vulgaris. The highest protein, carbohydrate,
chlorophyll, and carotenoid content were recorded inC. vulgaris,C. raudensis,C. sorokiniana, andD. salina, respectively.
N. oceanica accumulated high lipid content and omega-3 fractions (31.09%). However, C. hedleyi had the highest lipid
productivity (11.64g/L/day) compared to other microalgae. The best species for biodiesel production was C. vulgaris, with
a specific growth rate of 0.36 day−1, lipid productivity of 7.45g/L/day, and C16-C18 fatty acid profile of 78.3%. The micro-
algaeC. vulgarishad appropriate biodiesel properties of low viscosity (4.49), high cetane number (55.38), and relatively low
cloud point (4.98). Another choice was N. oceanic, with high lipid productivity, cetane number (59.79), oxidative stability
(56.43), and low iodine value (47.11). Microalgae T. bazangan sp. nov. had a cetane number (55.24), low cloud point (4.71),
and C16-C18 fatty acid profile of 82.34%. Accordingly,C. vulgaris,T. bazangan sp. nov., andN. oceaniccan be considered
potential species for biodiesel.
Keywords Biofuel· Chlorella vulgaris· Tetraselmis bazangan sp. nov.· Nannochloropsis oceanic· Fatty acid profile
Introduction
Global crude oil consumption has increased in the last
half-century due to rapid industrialization and population
growth [1]. The application of these fuels has destructive
effects, such as global warming, ecological degradation, and
health issues. The first and second generations of biofuels
were derived from food sources and cellulose derivatives.
However, the biofuels derived from soybean (Glycine max)
and canola (Brassica napus) have several disadvantages, for
example, high prices and increased greenhouse gas emission.
Lipid-rich microalgae can be used for biofuel and especially
biodiesel production, because their lipid yield being higher
than those of the best oilseed crops. Microalgae can be con-
sidered an alternative candidate for biofuel production and
the third generation of biofuels [2].
Microalgae, as a highly diverse group, are found in different
environments, such as freshwater and marine systems. They
are very efficient in collecting sunlight and converting it into
biochemical compounds, which causes them to have a higher
production rate than plants. The high percentage of valuable
compounds such as proteins, carbohydrates, pigment, lipids,
minerals, antioxidants, and vitamins in microalgae makes them
an excellent source for different industries, including medicine,
cosmetics, food, feed, and biofuel [1, 2]. Some algae are a good
selection for biodiesel production due to their high growth rate
and ability to store lipids. The lipid of algae is divided into
three groups according to lack, presence, and number of double
bonds (SFAs, MUFAs, and PUFAs) [3].
* Saeid Malekzadeh-Shafaroudi
malekzadeh-s@um.ac.ir
1 Department ofBiotechnology andPlant Breeding, Ferdowsi
University ofMashhad, Mashhad, Iran
2 Department ofBiology, Ferdowsi University ofMashhad,
Mashhad, Iran
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Photosynthetic microalgal pigments-chlorophylls, carotenoids, and phycobilins-are pivotal in microalgal biometabolite production, attracting significant bioprospecting interest [82]. Pigments are analysed after having been extracted using organic solvents [83] through spectrophotometric readings at pigmentspecific autofluorescence wavelengths, often using equations to extrapolate these reads for total pigment quantification [67][68][69]84]. Variations include HPLCbased quantification as seen in Grubišic, et al. (2022) or Patel, et al. (2022), who also extrapolated the total pigment content of their bioprospected microalgae by using established equations [70,78]. ...
... Similarly ineffective, current microalgal characterization methodologies require a biomass yield in the milligrams [107]. Ideally, this excruciating high biomass yield should be achieved with culture optimization but realistically, bioprospecting efforts do not progress beyond basic discriminations such as fresh or saltwater [70,84,86]. This presents a double-edged dilemma as, while rapid growth is a desirable trait, its relevance is diminished if the culture conditions used for its assessment do not match the future culturing parameters required at the prospective application of the strain. ...
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